This invention relates to a former for a reinforced concrete slab. More specifically, the invention relates to a removable former which is interlockable with other, similar formers between spaced-apart ribs to form shuttering between the ribs for a reinforced concrete slab.
Various different methods for forming reinforced concrete slabs exist. In block-and-rib type methods, the slab is formed by spanning a plurality of spaced-apart, steel reinforced, precast concrete ribs between vertical support members, placing filler blocks on top of the ribs so as to span across the gaps between adjacent ribs, locating additional steel reinforcing over and/or between the blocks, and casting concrete over the ribs and blocks.
Typically, the filler blocks are formed from a cementitious material such as a cement and sand mix. These blocks are normally relatively heavy and tend to be difficult to handle and transport. Furthermore, if the slab requires steel reinforcing which spans in two transverse directions, it is usually necessary to space the blocks from one another along the lengths of the ribs so as to accommodate the additional steel reinforcing. The openings defined between the spaced-apart blocks have to be closed off with additional shuttering before the concrete can be cast, and the erection of this additional shuttering usually involves a substantial amount of extra work and often is relatively time consuming. Another drawback associated with conventional filler blocks for block-and-rib reinforced concrete slabs is that they are incorporated into the slab during casting of the concrete and cannot be removed for subsequent re-use.
It is an object of the present invention to provide a removable former which can be used together with other, similar formers instead of filler blocks in a block-and-rib type reinforced concrete slab, which is interlockable with adjacent formers so as to allow steel reinforcing to span in two transverse directions between the formers without the need for any additional shuttering, and which is easy to handle and transport.